can: at91_can: RX queue could get stuck at high bus load
At high bus load it could happen that "at91_poll()" enters with all RX
message boxes filled up. If then at the end the "quota" is exceeded as
well, "rx_next" will not be reset to the first RX mailbox and hence the
interrupts remain disabled.
Signed-off-by: Wolfgang Grandegger <wg@grandegger.com>
Tested-by: Amr Bekhit <amrbekhit@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
diff --git a/drivers/net/can/at91_can.c b/drivers/net/can/at91_can.c
index 8b3275d..8f5e93c 100644
--- a/drivers/net/can/at91_can.c
+++ b/drivers/net/can/at91_can.c
@@ -712,9 +712,10 @@
/* upper group completed, look again in lower */
if (priv->rx_next > get_mb_rx_low_last(priv) &&
- quota > 0 && mb > get_mb_rx_last(priv)) {
+ mb > get_mb_rx_last(priv)) {
priv->rx_next = get_mb_rx_first(priv);
- goto again;
+ if (quota > 0)
+ goto again;
}
return received;